The correct answer is option 2, Starfish. Starfish are not considered true fish because they do not have typical fish characteristics. True fish have a streamlined shape, gills for respiration, fins for swimming, and scales for protection. Starfish, on the other hand, have a round body shape and move using their tube feet. They also have a water vascular system instead of gills and do not have traditional fins. While starfish may live in water and have a resemblance to fish, they are classified as echinoderms, not fish. Echinoderms are a separate group of marine animals that also include sea urchins and sea cucumbers.